Assembly:

Half Square Triangles

Mark the wrong side of four white 1 1/2″ squares in half diagonally once. Lay a marked white square over a red 1 1/2″ square, right sides together. Sew a quarter inch from each side of the marked line. Cut apart on the marked line and press.
Trim each Half Square Triangle to 1″ square. Make 8.

Repeat with four red 2″ and four white 2″ squares. Trim each Half Square Triangle to 1 1/2″ square. Make 8.

Repeat with two black 2″ and two white 2″ squares. Trim each Half Square Triangle to 1 1/2″ square. Make 4

Center

Sew a red 1″ square to the left side of a 1″ Half Square Triangle as shown. Make 2. Sew this unit to the top and the bottom of the red 1 1/2” square.

Sew a 1″ Half Square Triangle to either side of a 1” red square. Sew to the right side of the center unit. Sew another 1″ Half Square Triangle to the left side of the unit as shown. Make 2. Sew to the left and right sides of the red 1 1/2″ square.

Center unit measures 2 1/2″ square unfinished.

Block Assembly:

Lay out a black and a red 1 1/2″ Half Square Triangle as shown. Sew together and press. Make 4.

Using two of these pairs, sew to the left and right side of the Center unit.

Sew a red 1 1/2″ Half Square Triangle to each side of the Half Square Triangle pair as shown. Make 2.